/Engine/Source/Editor/SceneOutliner/Public/ISceneOutlinerHierarchy.h
class ISceneOutlinerHierarchy : public [TSharedFromThis< ISceneOutlinerHierarchy >](API\Runtime\Core\Templates\TSharedFromThis)
FHierarchyChang...
HierarchyChangedEvent
ISceneOutlinerM...
Mode